Preparation And Propotions Of CuO/ZnO Composite Nanomaterials

The important catalyst system, CuO/ZnO, has been widely used in organic reaction and a series of industrial catalytic reaction and has become a hot research topic. The synthetic methods of nanomaterials provide new opportunities to the synthesis of catalysts, but the high specific surface area of nanoparticles would lead to agglomerating at a high temperature, which then greatly decrease their catalytic activity. Thus, how to improve the stability and activity of CuO/ZnO becomes the key research issue. This dissertation mainly focus on this point. Fabricating the CuO/ZnO composite nanostructures to increase the combining degree of the two components and the dispersity of CuO allows to enhance the activity and stability of catalyst. Additionally, by controlling the proportion of copper and zinc in the composite structure will help us to explore the best catalyst.The main contents are listed as follows:(1) Three-dimensional spherical basic zinc carbonate were synthesized by a hydrothermal method by chossing an appropriate surfactant and a suitable mole ratio under a proper temperature. Its adsorption performance toward lead ion and methyl orange in water was further researched. The maximum adsorption amount is 1600mg/g and 45.3mg/g, respectively.(2) Based on the fact(KspZn(OH)x(CO3)y>KspCu(CO3)x(OH)y), CuO/ZnO composite nanomaterials were synthesized by an ion exchange method combined with calcination, using basic zinc carbonate prepared above as the precursor. Both copper and zinc dispersed evenly in the material, which has effectively improved the dispersity and adhesion strength between the two phases. With this method, the amount of Cu could be readily tunned by adjusting the molar ratio of the starting materials. In addition, the sample with a [Cu]/[Zn] ratio of 0.5667:1 had the highest catalytic activity in cyclooctene oxidation and the stability are higher than pure CuO. The above results show that this method is the effective route to improve the catalyst activity and stability.(3)(CuxZn1-x)(OH)m(CO3)n solid solution was prepared by ion coprecipitation and the CuO/ZnO composite was obtained after calcination. The results show that copper and zinc two elements are evenly dispersed in this material. And it also shows high catalytic activity and stability in cyclooctene oxidation reaction.